Question to users of the Century Focus Ring

Monglane

Monglane

Well-known member
Hi all,

So, I've installed my Century manual focus system on my DVX100A. First question : the focusing ring now moves a lot less smoothly than it did before. I assume that has to do with the various plastic parts of the Century system rubbing against each other. There's also some rubbing noise, whereas beforehand, the original focusing ring moved quite noiselessly.

Have you experienced those side effects as well ?

Secondly, and more importantly, I assumed the Century system would provide me with hard stops equivalent to focus 0 and focus 99 (inifinity), but in fact, what I got are hard stops at focus 0 and focus 60 or so.

As far as I can tell, I've assembled and set the whole system in accordance with the printed instructions that came with it.

Have I done something wrong ?

Thanks a lot in advance !


For those who wonder wxhat a Century manual focus ring is, see here : http://www.centuryoptics.com/products/prodv/dvx100/Manual_Focus/manual_focus.htm
 
Re: Question to users of the Century Focus Ring

yeah, the hard stops thing threw me off too... i usually just leave the macro switch on the thing off so it doesn't have stops...
 
Re: Question to users of the Century Focus Ring

The hard stops should be more like at 50 (or 37) and 95. Infinity is at 95, and 50 is the minimum object distance on a DVX100. I think the M.O.D. on a 100A is 37. 0 and 60 would be useless, you want to calibrate it so it's more like 37 and 95. You don't want to go past 95 or your shots will be out of focus at infinity.
 
Re: Question to users of the Century Focus Ring

I had the same problem with sticky focus. Try reinstalling the ring carefully and evenly. You'll be able to restore the even zoom.

erik bryan slavin
 
Re: Question to users of the Century Focus Ring

Tks, guys !

Kai : OK but it sort of defeats the purpose then, doesn't it ?

Erik : tks, I'll try that.

Barry : I fully agree with you (and I knws about focus 93 being equal to infinity), but... how did you get your focus ring to hard-stop at 93-94 and 50 (or 37) ? Did you just follow the (skeleton) instructions ? I can't for the life of me figure what I did wrong, if anything...
 
Re: Question to users of the Century Focus Ring

I don't have the ring, I've just seen it at NAB, so I don't have any real answers for you other than to say that it's supposed to have the hard stops implemented at M.O.D. and infinity, not at 0 and 60. So there should be some sort of calibration routine you can go through. Maybe you spin the ring to the infinity hard stop, and then push the auto infinity button, and that will calibrate it properly? Seems reasonable...
 
Re: Question to users of the Century Focus Ring

[quote author=Monglane link=board=Links;num=1089642795;start=0#4 date=07/12/04 at 13:07:40]

Kai : OK but it sort of defeats the purpose then, doesn't it ?
[/quote]

No, because I only needed it to link up with my follow focus.
 
Re: Question to users of the Century Focus Ring

OK, I finally did it, after much trial and error. It is nowhere as easy as it seems when you look at Century's instruction sheet, and I'm still not sure how exactly I eventually succeeded, although Barry's excellent suggestion to use the infinity button helped (I think).

I had half a mind to disassemble the whole thing to actually look into it and try and understand how it worked, but then I had spent quite some time adjusting and carefully balancing the tightening of the screws to obtain a tight fit without excessive drag and plastic noise when focusing, and I didn't want to have to go through that process again.

Anyway, I now have hard stops at 40 and 93, but I dare not switch to Macro range for fear of losing my settings and having to start all over again...

Bottom line, IMHO : the Century ring is an excellent product, but be prepared to spend quite some time setting it up. It is NOT straightforward, nor is it easy.

Also, the significant increase in front part of the lens barrel diameter means that the camera does not rest evenly on its base like before : when you set it on a flat surface, the front rests on the focusing gear. The added strain is probably minimal, but somehow it "hurts" me to see it lying all tilted up like that... :'(
 
Re: Question to users of the Century Focus Ring

I actually wrote Ken Robings who works for Century Optics for a more detailed instruction set then what is provided on their website. I agree with you there - very minimal read those instructions.

For one thing - and I think I mentioned this somewhere else, sorry if I'm repeating - you don't want to screw that split ring flush together. When they cut that ring in half, about a millimeter's worth of material is removed so you need to leave about a fingernail's width between the top and bottom ring. This should give you the best balance between having a tight fit and yet be able to move the focus ring freely.

Also, a warning. If you change around a lot from manual to auto focus, you may have to recalibrate the ring. I have to test again, but this may also be true if you switch between scene files a lot. I'll test this week and get back to you but in the meanwhile, here is a post I found and saved from DVInfo written by Nathan Clapp that I found useful:

"So, after using the CP ring for a bit- here are my impressions- Excellent for repeatable focus marks, and allows focus gears for follow focus units to be installed either for onboard ff units or remote operation like on cranes.

Ring is purely mechanical

Ring takes about 10-15 min to install.

Ring has a "lockout" for macro stuff- anything below 53 "Panasonic focus units" is in the "Macro" setting. Once you calibrate ring- the only way for miscalibration is to spin it into macro (after flipping switch) and spin it below 00 or spin it back into macro and take it to 99+ w/o flipping macro lockout switch back on.

Also- I just learned do not have Focus in auto focus even in 24p- because as camera powers up it messes with the last "position" of the numbers for focus causing you to have to recalibrate focus unit.
HOW TO RECALIBRATE: Just put the switch to macro- allows full rotation of focus. spin until you get to 99, throw macro lockout switch and spin until ring stops- now 99 equals physical stop on lens- and 99-53 are fully repeatable and with some caution 00-99 is also fully repeatable.

Maybe not so user friendly in handheld as finges must go on geared teeth of ring, but that is a personal pref. some like it a lot."
 
Re: Question to users of the Century Focus Ring

Tks, Oz, that was very interesting. I look forward to reading about your upcoming tests.
 
Re: Question to users of the Century Focus Ring

I cancelled my order for the Century Gear. When my Chrosziel kit arrived they supplied their own gear ring which works perfectly.
 
Re: new cinestyle ring coming out for 100a users!

Re: new cinestyle ring coming out for 100a users!

monglane, i have just confirmed from 2 different resellers that a NEW version of the cinestyle focus ring will be coming out.  it will be better suited for the dvx100a as well as work w/the original dvx100.  this could be why you have this problem.  so for 100a users, i'd hold off until the new one comes out in a few weeks.  
 
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